Develop Reference

Android XML Elements and Namespaces

Is it not possible to simplify the name of a custom element in an Activity XML file?
<com.library.CustomView
xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:app="http://schemas.android.com/apk/res/com.example.library.customview"
android:id="#+id/myView"
app:newAttr="value" />
Say for example I have a CustomView control. Do I always have to put "com.library." in front of "CustomView" or is it possible to use xmlns:custom in a FrameLayout so that I don't need to?
This is what I would like to see (if possible):
<CustomView
xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:app="http://schemas.android.com/apk/res/com.example.library.customview"
android:id="#+id/myView"
app:newAttr="value" />

No. You must specify the fully qualified name of the custom view class. The custom attribites belong to a different namespace. So you nee to have
http://schemas.android.com/apk/res/[your package name].
That is why you have
xmlns:app="http://schemas.android.com/apk/res/com.example.library.customview"
It is necessary to specify fully qualified name of the custom view and hence
<com.library.CustomView
http://developer.android.com/training/custom-views/create-view.html
The docs does not mention any other solution.
Edit:
There seems to be a workaround as mentioned in the below link. Notice comments on both answers. The authors feels there is a little overhead involved. So its left you to use the below although i recommend you to follow the above method mentioned in the docs.
Using custom Views in XML without using fully-qualified class name

Android: Control with own parameters

I want to ask you, if is possible in Android to make a control, which will take my own parameters.
I want, that my control will looks like:
<my.own.control
android:style
attributes
>
<include name=”” value=””>
<include name=”” value=””>
</my.own.control>
or
<my.own.control
Android:style
attributes
>
<include>
<name></name>
<value></value>
</include>
<include>
<name></name>
<value></value>
</include>
</my.own.control>
The reason why I want to do it this way, is to dynamically edit includes.
The most important question is, how to read includes on initialize.
Or do you have another advice?

Unfortunately this is not possible.
There is an open bug on the android project for it that was reviewed and accepted by Romain-gui, one of the lead android developers at google.
http://code.google.com/p/android/issues/detail?id=14532
There is however a workaround, it is explained very well at http://kevindion.com/2011/01/custom-xml-attributes-for-android-widgets/

Android custom attributes on "normal" views?

After taking a look at theming for Fede's UberMusic I came across the file album_screen.xml. Below is the source of that file. Basically I noticed that his themes have the ability to use custom views that are a part of his application, and that they have this XML namespace at the top theme. I am missing the connection as to how he is able to apply his attributes to views that he does not control, and how Eclipse will compile the cod below without fail. I placed the URL http://schemas.uberdroidstudio.com/theme into my browser's address bar but nothing came up, and I cannot figure out where/ how Eclipse knows the attributes that the namespace supports. Thank you ahead of time for your help.
<?xml version="1.0" encoding="utf-8"?>
<merge
xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:theme="http://schemas.uberdroidstudio.com/theme">
<TextView
android:id="#id/artist"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_weight="0.0"
theme:textFilter="uppercase" /> <!-- This is the interesting line -->

I suspect that the theme:textFilter="uppercase" line isn't actually having an effect on the (apparently vanilla) TextView.
As for the URL of the namespace, it is interesting that you can't access it, since it does not appear to be a local styleable (Android would have you refer to a local styleable namespace as http://schemas.android.com/apk/res/your.package). +1 for novelty.

The solution is actually not as complicated as I originally thought. XML namespaces are arbitrary strings that just need to be unique. If your namespace does not start with http://schemas.android.com/apk/res then it is not validated and the APK package is not checked for declare-styleable or the like.
Now a custom namespace if very simple to implement, as illustrated by this code snippet in GitHub. Finally, applying custom XML attributes to "normal" widgets can be accomplished by using the LayoutInflater.Factory and calling setFactory before you inflate your views. Throw it all together and you have a highly theme-able, XML driven application like Fede's UberMusic.

Can I create a statich part of view

I`m wondering about one thing. If I decide to have a part of my View same in every Intent. For example 2 buttons at the bottom of screen and for example I have 3 diffrent views, List, Detail and a third one :) Do I need to put the buttons on every xml schem for each view or can I create other xml and attach it in each activity with all listener etc.
If I can attach in activity how can I do that ?

Create a XML buttons.xml with the common elements
<merge xmlns:android="http://schemas.android.com/apk/res/android">
<ImageButton
android:id="#+id/myButton"
android:src="#drawable/ic_title_search"
android:onClick="myHandle" />
<ImageButton
android:id="#+id/myButton2"
android:src="#drawable/ic_title_search"
android:onClick="myHandle" />
</merge>
Include it in another xml:
<include layout="#layout/buttons"/>
where buttons is the name of the xml file to be included

You can use the <include /> tag in your XML files.
See Layout Tricks for an example.

Create a separate layout for your buttons then in the layout you wish to display them use the include tag.
This will allow you to reuse the same layout in multiple parent layouts.

The include works as stated above you could also consider using fragments
Fragments
You can use these in older versions of Android by including the compatibility library in your application. It's definitely more work than a simple include but if you need some reusable UI for more sophisticated features than simple buttons you might want to look at that as well
How to use compatibility API

Emulate android preference category look/feel

I like the title bar style from the Android preference category.
In my Activity (not a PreferenceActivity) How can I use the same style?

Since I just spent the last few hours trying to answer this old question, I'll do it here for anyone else.
It turns out the resource the preference category style is using is listSeparatorTextViewStyle.
You use it like this:
<TextView
android:layout_width="fill_parent"
android:layout_height="wrap_content"
android:text="Hello, World"
style="?android:attr/listSeparatorTextViewStyle"/>
Using style="?android:attr/preferenceCategoryStyle" didn't work.

The main layout is most likely a ScrollView with a LinearLayout. As for the individual layout, I believe (just guessing after looking at the documentation) that you can use the various attributes in android.R.attr - look here: http://developer.android.com/reference/android/R.attr.html. There are attributes like preferenceCategoryStyle, preferenceStyle, etc. You can apply any style to any of your views.